Superstar, miley cyrus is opening up in a candid interview, revealing brand-new engagement to her heartthrob, liam hemsworth, her relationship with her dad, and how she is shaping up and slimming down. Linsey davis is here with that story. orter: GOOD MORNING, AMY. Cyrus remains tight-lipped on how her fiance popped the question. But the acting, singing teen sensation gives details on what happened to her curves to the carats on her ring finger. Miley cyrus is sporting a new bob, bling and hair to match. Her latest flame, liam hemsworth, her soon-to-be hubby. We've been together for a long time. And I know this is what I went for my life. Life is too short not to spend every moment not spending the person who makes you happy as happy in return. ♪ I look at you ♪ Reporter: The 19-year-old singer says she was completely surprised when hemsworth, her boyfriend of three years, popped the question, in their l.A. Home. Even her parents didn't know about it. Though cyrus admits she's seen a similar ring online and told hemsworth it was pretty. "Marie claire's" joyce chang was with cyrus an hour after she heard the news. And she says the starlet was over the moon. She couldn't have been happier with the ring. She said, he did really good. Reporter: These days, the diamond is far from the only thing that looks different about cyrus. The former brunette-turned blonde, was once criticized for her weight. But now, has a washboard stomach. She credits pilates, which she posted this twitter pic. That's being comfortable with who you are. Iver gotten more comfortable with that. Reporter: "Marie claire" is quick to point out the change, too. Saying cyrus bears about as much resemblance to herself as a mojito to lemon aid. There's more zing to it and more spice to it. And she's not hannah montana anymore. Reporter: As far as the nuptials, she says they're in no rush. They want to have a long engagement. She doesn't care about the wedding or the piece of paper, as much as the promise they've made to each other. This edition of "marie claire" HITS STANDS AUGUST 19th. Thank you so much.

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